scholarly journals Production of Douglas-Fir in the Czech Republic based on national forest inventory data

2013 ◽  
Vol 59 (No. 10) ◽  
pp. 398-404 ◽  
Author(s):  
V. Podrázský ◽  
R. Čermák ◽  
D. Zahradník ◽  
J. Kouba
Keyword(s):  
Czech Republic ◽  
Tree Species ◽  
Forest Inventory ◽  
National Forest Inventory ◽  
Douglas Fir ◽  
National Forest ◽  
Northern Red Oak ◽  
Forest Land ◽  
Land Area ◽  
The Czech Republic

This article summarizes basic estimates of productivity and trend analysis of one of the principal introduced forest tree species in the Czech Republic, i.e. Douglas-fir (Pseudotsuga menziesii [Mirbel] Franco). As a comparison, we also examine grand fir (Abies grandis [D. Don] Lindl), northern red oak (Quercus rubra L. syn. Quercus borealis Michx.) and black locust (Robinia pseudoacacia L). This paper presents estimates of forest land area, standing volume, annual and total increments, distribution of age classes, average ages and site indexes for the period 1979–2010. All data were obtained from the national forest inventory of the Czech Republic. Korf’s growth function was used for the assessment of current and mean annual increments (CAI, MAI) of Douglas-fir compared to other tree species. Our results suggest a decline in the annual area afforested by Douglas-fir, as influenced by the State administration management choices, a low rate of an increase in the forest land area, increasing average age of the forests. On the other hand, we observed a dramatic increase in the standing volume as well as high annual increments in volume. Douglas-fir is the most productive major tree species in the Czech Republic and there is a great potential to expand its use throughout the country.

scholarly journals Evaluation of silver birch diameter increment model based on data of the Czech National Forest Inventory

2020 ◽  
Vol 66 (No. 11) ◽  
pp. 471-481
Author(s):  
Jan Kikal ◽  
Zdeněk Adamec
Keyword(s):  
Czech Republic ◽  
Forest Inventory ◽  
National Forest Inventory ◽  
Forest Vegetation ◽  
National Forest ◽  
Vegetation Zone ◽  
The Czech Republic ◽  
Diameter Increment ◽  
Breast Height ◽  
Diameter Increment Model

In the Czech Republic, the silver birch (Betula pendula Roth.) is considered as a pioneer and a soil preparing tree species. It occurs mainly on clearcutting areas after disturbances. The aim of this study was to fit breast height diameter increment model for birch with respect to tree age, share of birch trees and forest site type (ecological series – ES and forest vegetation zones – FVZ). We used data of both cycles of National Forest Inventory of the Czech Republic. We evaluated production potential of this species. We tested Korf and Michailoff increment models in variant of nonlinear least squares model (NLS) and nonlinear mixed effects model (NLME). Michailoff models performed better. We found seven statistically significant and practically applicable models. The greatest influence on increment of diameter at breast height have forest vegetation zone and ecological series whereas the influence of the share of birch in forest stand is smaller. The highest absolute values of diameter increment were on gleyed or enriched with water sites in the fourth forest vegetation zone.

scholarly journals Land category in the National Forest Inventory of the Czech Republic

2010 ◽  
Vol 58 (5) ◽  
pp. 223-232
Author(s):  
Miloš Kučera
Keyword(s):  
Czech Republic ◽  
Forest Inventory ◽  
National Forest Inventory ◽  
National Forest ◽  
Special Focus ◽  
Land Classification ◽  
The Czech Republic ◽  
Definition Of

The article deals with the land categorization with special focus on the definition of category FO­REST in the National Forest Inventory of the Czech Republic (NFI CR). Definitions of land categories used in the first cycle of forest inventory in 2001–2004 are evaluated. The first task is to assess the appropriateness of existing land categorization and definition of category FOREST in terms of suitability of used parameters defining individual categories and their values. Their compatibility with international definitions of category FOREST is also assessed. The second task is, based on data from the first cycle of NFI CR, to calculate the area of category FOREST according to the international definition of European National Forest Inventory Network (ENFIN) and to determine whether the area of category FOREST is the same or varies from the area according to the definition FOREST defined in NFI CR.In the first part there is a list of used land classifications in the Czech Republic and there are also described used international classifications. Land categorization and definitions according ENFIN are presented. Further the parameters are chosen in the national definition of NFI CR, which are compared with analogous parameters defined by ENFIN, indicating differences. Subsequently, the area of category FOREST is calculated according to the parameters of national definition and ENFIN definition. Finally, suggestions are given for the land classification into categories for the second cycle of NFI CR, including the appropriate parameters and their values for the definition of category FOREST. Possible ways of their implementation into the methodology of NFI CR are listed.

scholarly journals Regeneration and game damage in the Krušné hory Mts. assessed on the basis of National Forest Inventory of the Czech Republic

2009 ◽  
Vol 55 (No. 6) ◽  
pp. 279-292 ◽  
Author(s):  
L. Lehnerová ◽  
R. Marušák
Keyword(s):  
Czech Republic ◽  
Forest Inventory ◽  
National Forest Inventory ◽  
Recent Measurement ◽  
National Forest ◽  
Measurement Standard ◽  
The Czech Republic ◽  
Standard Methodology ◽  
Extensive Information ◽  
Information Database

In 2001–2004 National Forest Inventory was realized in the Czech Republic. A great number of variables was measured giving rise to an extensive information database that can be used to assess the state and development of various quantitative and qualitative dendrometric characteristics. This work presents the results of regeneration state and game damage in the Krušné hory Mts. based on the data from both the National Forest Inventory and the second enlarged measurement carried out after five years that was done in a part of the Fláje preserve and enabled basic comparison with the rest of the area. For the calculation of data acquired in the old and recent measurement standard methodology for processing National Forest Inventory was used. Comparison of data showed that the average number of regeneration individuals dropped by more than a third in the interval of 5 years, as well as the number of plots with regeneration; game damage of regeneration also was lower by 4%. The proportion of individuals damaged by peeling did not change during the investigated period. A significant increase in game damage to regeneration was found in the Fláje preserve.

scholarly journals Economic Impact of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) production in the Czech Republic

2014 ◽  
Vol 60 (No. 7) ◽  
pp. 297-306 ◽  
Author(s):  
K. Pulkrab ◽  
M. Sloup ◽  
M. Zeman
Keyword(s):  
Czech Republic ◽  
Economic Impact ◽  
Pseudotsuga Menziesii ◽  
Tree Species ◽  
Economic Effect ◽  
Douglas Fir ◽  
European Countries ◽  
Natural Conditions ◽  
The Czech Republic ◽  
Forest Production

The article addresses the issues of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) production in the Czech Republic (CR). Our analysis shows that the tree species can occupy 149,616&ndash;163,713 ha in the CR (with respect to ecological limits set by the Czech legislation). The potential economic effect expressed by the gross yield of forest production might be higher by 27&ndash;30 million EUR&middot;yr<sup>&ndash;1</sup>.&nbsp; The results of the analysis support the forest owners&rsquo; interest to extend Douglas-fir production in the CR, similarly like it has been extended systematically in all European countries where natural conditions allow. &nbsp;

scholarly journals Remote-sensing support for the Estonian National Forest Inventory, facilitating the construction of maps for forest height, standing-wood volume, and tree species composition

2020 ◽  
Vol 73 (1) ◽  
pp. 77-97
Author(s):  
Mait Lang ◽  
Allan Sims ◽  
Kalev Pärna ◽  
Raul Kangro ◽  
Märt Möls ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Species Composition ◽  
Tree Species ◽  
Forest Inventory ◽  
Point Clouds ◽  
National Forest Inventory ◽  
National Forest ◽  
Tree Species Composition ◽  
Wood Volume ◽  
Forest Height

Abstract Since 1999, Estonia has conducted the National Forest Inventory (NFI) on the basis of sample plots. This paper presents a new module, incorporating remote-sensing feature variables from airborne laser scanning (ALS) and from multispectral satellite images, for the construction of maps of forest height, standing-wood volume, and tree species composition for the entire country. The models for sparse ALS point clouds yield coefficients of determination of 89.5–94.8% for stand height and 84.2–91.7% for wood volume. For the tree species prediction, the models yield Cohen's kappa values (taking 95% confidence intervals) of 0.69–0.72 upon comparing model results against a previous map, and values of 0.51–0.54 upon comparing model results against NFI sample plots. This paper additionally examines the influence of foliage phenology on the predictions and discusses options for further enhancement of the system.

scholarly journals Prediction and model-assisted estimation of diameter distributions using Norwegian national forest inventory and airborne laser scanning data

2021 ◽  
Author(s):  
Janne Räty ◽  
Rasmus Astrup ◽  
Johannes Breidenbach
Keyword(s):  
Tree Species ◽  
Forest Inventory ◽  
Laser Scanning ◽  
National Forest Inventory ◽  
Airborne Laser Scanning ◽  
Systematic Sampling ◽  
National Forest ◽  
Prediction Errors ◽  
K Nearest Neighbor ◽  
Airborne Laser

Diameter at breast height (DBH) distributions offer valuable information for operational and strategic forest management decisions. We predicted DBH distributions using Norwegian national forest inventory and airborne laser scanning data and compared the predictive performances of linear mixed- effects (PPM), generalized linear-mixed (GLM) and k nearest neighbor (NN) models. While GLM resulted in smaller prediction errors than PPM, both were clearly outperformed by NN. We therefore studied the ability of the NN model to improve the precision of stem frequency estimates by DBH classes in the 8.7 Mha study area using a model-assisted (MA) estimator suitable for systematic sampling. MA estimates yielded greater than or approximately equal efficiencies as direct estimates using field data only. The relative efficiencies (REs) associated with the MA estimates ranged between 0.95–1.47 and 0.96–1.67 for 2 and 6 cm DBH class widths, respectively, when dominant tree species were assumed to be known. The use of a predicted tree species map, instead of the observed information, decreased the REs by up to 10%.

scholarly journals Das Potenzial der Totholzakkumulation im deutschen Wald | Potential of deadwood accumulation in German forests

2010 ◽  
Vol 161 (5) ◽  
pp. 171-180 ◽  
Author(s):  
Franz Kroiher ◽  
Katja Oehmichen
Keyword(s):  
Tree Species ◽  
Forest Inventory ◽  
Decay Constant ◽  
Dead Wood ◽  
Large Diameter ◽  
Timber Harvesting ◽  
National Forest Inventory ◽  
Time Span ◽  
National Forest

Deadwood is an important part of the forest ecosystem. The quantity available depends on the rates of accumulation and of decomposition. A comprehensive pool of data regarding the deadwood stock for Germany is collected by the German national forest inventory. Moreover, the Projection Modelling of Forest Development and Timber Harvesting Potential (WEHAM) adds other important parameters such as growth rates and potential roundwood availability. Using this data, scenarios for the accumulation of deadwood were developed. For the calculation of deadwood decomposition, independent of tree species, a decay constant k = 0.054 was derived for the whole of Germany. The study shows that a long-term stop in timber harvesting in Germany, assuming the proportions of different tree species remained constant, would lead to a saturation of deadwood with a total of 184 m3/ha. If the German forest presented a natural composition of tree species, a deadwood stock of 150 m3/ha at most could be accumulated. Based on these scenarios, rates of accumulation of total dead-wood and of deadwood of large diameter can be calculated taking into account the deadwood stock levels desired and the time span involved. It has been shown that 7.3% of the WEHAM potential roundwood availability must remain in the forest per year if the quantity of deadwood is to be maintained at 11.5 m3/ha. If an increase in the accumulation of deadwood is to be aimed for, the annual input rate together with the desired deadwood stocks are increasingly influenced by the time span involved. Thus shorter time spans with greater stocks of deadwood to be achieved make it possible to approach the WEHAM potential roundwood availability. The results presented in this paper should assist in decision-making concerning stocks of deadwood to be aimed for in the forest and, in the future, serve as a basis for the selection, evaluation and discussion of quantities of dead-wood to be achieved.

The Norwegian Forest Resource Map SR16: Mapping Forest Attributes Using Heterogeneous Sets of Airborne Laser Scanning and National Forest Inventory Data

2021 ◽  
Author(s):  
Marius Hauglin ◽  
Johannes Rahlf ◽  
Johannes Schumacher ◽  
Rasmus Astrup ◽  
Johannes Breidenbach
Keyword(s):  
Tree Species ◽  
Forest Inventory ◽  
Laser Scanning ◽  
National Forest Inventory ◽  
Mixed Effects ◽  
National Forest ◽  
Forest Resource ◽  
Airborne Laser ◽  
Maturity Class ◽  
Species Specific

Abstract Background The Norwegian forest resource map SR16 combines national forest inventory (NFI) and airborne laser scanning (ALS) data. While the ALS data were acquired over a time interval of 10 years using various sensors and settings, the NFI data are continuously collected. Aims of this study were to analyze the effects of stratification on models linking remotely sensed and field data, and assess the accuracy overall and at the ALS project level. Material and methods The model dataset consisted of 9203 NFI field plots and data from 367 ALS projects, covering 17 Mha and ⅔ of the productive forest in Norway. Mixed-effects regression models were used to account for differences among ALS projects. Two types of stratification were used to fit models: 1) strata by the three main tree species groups spruce, pine and deciduous resulted in species-specific models that can utilize a satellite-based species map for improving predictions, and 2) a stratification by species and maturity class resulted in stratum-specific models that can be used in forest management inventories where each stand regularly is stratified accordingly. Stratified models were compared to general models that were fit without stratifying the data. Results The species-specific models had relative root-mean-squared errors (RMSEs) of 35, 34, 31, and 12% for volume, aboveground biomass, basal area, and Lorey’s height, respectively. These RMSEs were 2-7 percentage points (pp) smaller than those of general models. When validating using predicted species, RMSEs were 0-4 pp smaller than those of general models. Models stratified by main species and maturity class further improved RMSEs compared to species-specific models by up to 1.8 pp. Using mixed-effects models over ordinary least squares models resulted in a decrease of RMSE for timber volume of 1.0 – 3.9 pp, depending on the main tree species. RSMEs for timber volume ranged between 19 – 59% among individual ALS projects.Conclusions The stratification by tree species considerably improved models of forest structural variables. A further stratification by maturity class improved these models only moderately. The accuracy of the models utilized in SR16 were within the range reported from other ALS-based forest inventories, but local variations are apparent.

scholarly journals Large scale mapping of forest attributes using heterogeneous sets of airborne laser scanning and National Forest Inventory data

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Marius Hauglin ◽  
Johannes Rahlf ◽  
Johannes Schumacher ◽  
Rasmus Astrup ◽  
Johannes Breidenbach
Keyword(s):  
Tree Species ◽  
Forest Inventory ◽  
Laser Scanning ◽  
National Forest Inventory ◽  
Mixed Effects ◽  
Airborne Laser Scanning ◽  
National Forest ◽  
Airborne Laser ◽  
Maturity Class ◽  
Species Specific

Abstract Background The Norwegian forest resource map (SR16) maps forest attributes by combining national forest inventory (NFI), airborne laser scanning (ALS) and other remotely sensed data. While the ALS data were acquired over a time interval of 10 years using various sensors and settings, the NFI data are continuously collected. Aims of this study were to analyze the effects of stratification on models linking remotely sensed and field data, and assess the accuracy overall and at the ALS project level. Materials and methods The model dataset consisted of 9203 NFI field plots and data from 367 ALS projects, covering 17 Mha and 2/3 of the productive forest in Norway. Mixed-effects regression models were used to account for differences among ALS projects. Two types of stratification were used to fit models: 1) stratification by the three main tree species groups spruce, pine and deciduous resulted in species-specific models that can utilize a satellite-based species map for improving predictions, and 2) stratification by species and maturity class resulted in stratum-specific models that can be used in forest management inventories where each stand regularly is visually stratified accordingly. Stratified models were compared to general models that were fit without stratifying the data. Results The species-specific models had relative root-mean-squared errors (RMSEs) of 35%, 34%, 31%, and 12% for volume, aboveground biomass, basal area, and Lorey’s height, respectively. These RMSEs were 2–7 percentage points (pp) smaller than those of general models. When validating using predicted species, RMSEs were 0–4 pp. smaller than those of general models. Models stratified by main species and maturity class further improved RMSEs compared to species-specific models by up to 1.8 pp. Using mixed-effects models over ordinary least squares models resulted in a decrease of RMSE for timber volume of 1.0–3.9 pp., depending on the main tree species. RMSEs for timber volume ranged between 19%–59% among individual ALS projects. Conclusions The stratification by tree species considerably improved models of forest structural variables. A further stratification by maturity class improved these models only moderately. The accuracy of the models utilized in SR16 were within the range reported from other ALS-based forest inventories, but local variations are apparent.

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